The phylum Ctenophora is a relatively small phylum of about 150 valid species, or even less depending on who you ask. They are actually not related to Cnidarians or Jellyfish even though both Ctenophores and Jellyfish are loosely referred to as jellies. Defining features include biradial symmetry, sticky cells (colloblasts),an aboral sense organ, rows of cillial band, and instead of a regular nervous system they have a non centralized net (Much like Cnidarians!!!).
There’s 3 main types of Ctenophores:
Cypiddids which have round bodies, sometimes spherical or oval with branched tentacles that they can bring back into pouches near their mouth.
Beroids who have no tentacles, are sack shaped and have a huge mouth that can be shut extremely tight. They eat by engulfing their prey
Lobates which are larger than Cypiddids and are classified by the flat lobes below their mouth and their short tentacles.
There is other types of bodily forms Ctenophores can take like Thalassocalyce (Similar to medusae in shape), Ganeshida ( Circular instead of oval and the pharynx extends over the inner surface of their lobes), and Cestida (Belt like or ribbon like shape). An example of an organism classified under Cestida is the Venus Girdle, one of the largest ctenophores known.
